How did stegosaurus mate? Very inventively

DINOSAURS with spiky backs or tails may have had sex in a prehistoric variant on the missionary position to prevent injury, castration or even death, scientists believe.

New research has challenged the belief that the prehistoric beasts all had sex the same way, with the male mounting the female from behind.

For some dinosaurs, particularly herbivores such as stegosaurus, which had a stiff, spiky tail, such a position could have proved dangerous or even fatal.

“The females could not raise their tails because the bones at the top end were fused,” said Brian Switek, a dinosaur researcher and writer, whose book My Beloved Brontosaurus comes out soon. “Also, some species had lethal spikes on their backs, which would have been impossible to get past.”

Heinrich Mallison, a scientist at the Museum of Natural History in Berlin, has designed computer models of kentrosaurus, a cousin of stegosaurus, to see if males